近日，荷兰莱顿大学Marc T. M. Koper团队研究了阶梯铂电极双电层的综合模型。2026年2月2日出版的《自然-化学》杂志发表了这项成果。

理解阶梯铂电极的双电层结构对于认识电催化相关铂电极（通常由复杂取向的晶面、台阶和缺陷混合构成）的反应环境至关重要。

研究组通过周期性引入（110）型或（100）型台阶对（111）平台区进行结构调控，系统探究了这类表面的双电层结构。发现在0.1 mM HClO4溶液中，微分电容最小值Cd,min表现出显著的结构敏感性。研究组将这一现象归因于（110）与（100）晶面在水解离亲和力上的本质差异。

通过连续介质模型验证，确认对于（110）阶梯系列，Cd,min对应的电势Ed,min可近似视为零自由电荷电势Epzfc。结合从头算分子动力学模拟，研究组揭示了台阶位点吸附的OH物种导致Epzfc与功函数之间呈现不同于台阶密度的变化规律。该研究构建了阶梯铂表面双电层结构的统一理论框架，弥合了理想单晶模型表面与实际多相铂电极之间的认知鸿沟。

附：英文原文

Title: A comprehensive model for the electric double layer of stepped platinum electrodes

Author: Frhlich, Nicci L., Liu, Jinwen, Ojha, Kasinath, Hagopian, Arthur, Doblhoff-Dier, Katharina, Koper, Marc T. M.

Issue&Volume: 2026-02-02

Abstract: Understanding the electric double layer (EDL) of stepped Pt electrodes is crucial for comprehending the reaction environment for electrocatalytically relevant Pt electrodes, which typically comprise a complex mixture of facet orientations, steps and defects. Here we systematically investigate the EDL structure of these surfaces by periodically perturbing (111) terraces by either (110)- or (100)-type steps. We find that the minimum in the differential capacitance Cd,min in 0.1mM HClO4 is highly structure sensitive. We attribute this observation to inherent differences in affinity for H2O dissociation between (110) and (100) facets. Using a continuum model, we confirm that the potential of Cd,min (Ed,min) closely approximates the potential of zero free charge Epzfc for the (110)-stepped series. Together with ab initio molecular dynamics simulations, we reveal that OHads at step sites leads to a different step-density-dependent trend between Epzfc and the work function. Our approach yields a unified picture of the EDL structure on stepped Pt surfaces, bridging the gap between model single-crystal surfaces and practically relevant heterogeneous Pt electrodes.

DOI: 10.1038/s41557-025-02063-9

Source: https://www.nature.com/articles/s41557-025-02063-9